Roughly how many gallons a week do you expect to be processing, or are you making a general question about a career choice?

There are a few ways of doing it, each with different capital cost, running cost and quality of silver recovered. You can recover silver from bleach and fixer.

The first part of the course could be how to Google 'silver recovery fixer'. That will give you a lot of information. A general chemical engineering / extractive metallurgy related course would be OK - what level of education are you at / do you expect to be at?

If all you are interested in doing is recovering silver from photo chemicals, I don't see why you think you need a degree. Get some chemistry and science books, talk to some chemical engineering profs or students, basic electrolysis is pretty straight forward stuff.